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Thank you very much for your help! Me too not a expert of OpenGL but sure, you know it better than me becuse i am new in OpenGL and my English isn't very good to understand everything.
Oh, i am an idiot First, I might say thats:
Already, I called Screenshot function with screen surface and drew something to screen.The problem weren't them.
When i tried GL_FRONT_LEFT, i made it just and i have a question: why doesn't it be when i tried GL_FRONT_RIGHT instead?
What is different between LEFT and RIGHT? Does it mean front face and back face. I will try all of them.

You spoke to a interesting point about old games. Why the old games work less quality on newer computers? I think, maybe the reason is developers's a premeditation or mismatchs between old versions and new versions. I don't know which one but me too wonder.

Yes, me too, i want to make my own game engine.Mine will be with SDL and OpenGL in C.Now, if i want, i can use them to draw nice 3D/2D graphics but i still haven't got enough knowledge about them for advanced drawing so i must learn things more than them.At the moment, i am working on sound system.So far i tried a function to load and play a sound file(.wav) from a folder.I am very happy now becuse it played !

Yes, i know but when i put glDisable(GL_DEPTH_TEST) to initialization, the red box looked on the transparent letter "A"(my 2D Ortho graphic).I think, the box must be under the 2D letter.
This is screenshot when i put glDisable(GL_DEPTH_TEST);